Greeting card envelopes have typically been considered as strictly a protective packaging or storage device for a greeting card. Most greeting card envelopes are the standard 5¾ by 8¾ white envelope in which a greeting card may be inserted for delivery. Most advances in this area have involved the greeting card. Greeting cards have become more entertaining with advances in printing and with the advent of small portable data storage devices. Sound has been added to greeting cards to increase the personalization of cards by delivering an audio message that is electronically embodied in circuitry that is carried within the greeting card. The ability to use sound in combination with printed matter such as with conventional printed greeting cards significantly enhances the communicative value of social and relational greetings. The use of popular music and celebrity voice impersonations has made sound-generating greeting cards increasingly popular.
More recently, envelopes have started to be considered a decorative aspect of or complimentary to the envelope contents. Considering that envelopes very often do not contain a greeting card but perhaps a handwritten note or gift card, more thought has been given to the decorative or entertainment aspect of the envelope. Given that most envelopes are made of paper or paper-like material, they are intrinsically amendable to embellishment with text, graphics, size, shape, color, texture and design. The sound or audio envelope functions both as an envelope and as a sound-generating, entertainment or message-carrying device independent of or in connection with its contents.